<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<form action="javascript:alert('hello')">
    Username:<input type="text" name="username" id="username"><br>
    Password:<input type="password" name="pwd" id="pwd"><br>
    <input type="submit" name="submit" id="submit">
</form>
</body>
</html>